Method of using laser-induced optoacoustics for the treatment of drug-resistant microbial infections

ABSTRACT

The present invention is related to novel functional antibody coated nanoparticles, and the preparation method thereof. The functional antibody coated nanoparticles according to the present invention can be used as photothermal agents to effectively inhibit the growth of microbes including drug-resistant strains and biolfilm with laser irradiation.

BACKGROUND OF INVENTION

A major cause of serious battlefield injuries during Operations IraqiFreedom and Enduring Freedom has been the use of improvised explosivedevices against coalition troops. Maxillofacial, head, and neck regionsare particularly at risk for injury and pose distinct treatmentchallenges to clinicians (1, 2). These combat associated traumaticwounds are different from injuries experienced in the civilian sectordue to massive tissue damage from extremely high velocity, high-energyprojectiles, involvement of blast wave effects, and a higher rate ofwound contamination from the environment (2). Previous studies indicatea significant percentage of these wounds were infected with multi-drugresistant bacteria such as methicillin resistant Staphylococcus aureus(MRSA) (1). In addition to those injured in combat, military recruitsare one of the groups identified as at risk for acquiring MRSAinfections. This is notable because those affected are typically young,healthy individuals without any apparent risk factors, and theseinfections have been associated with an increased incidence ofhospitalizations. Because emergence of multi-drug resistant bacterialinfections is a growing problem in military and civilian populationsworldwide, novel anti-microbial therapies are needed as alternatives totraditional antibiotic regimens.

Current treatment regimens for bacterial infections focus on use ofantibiotics. The challenges associated with the successful treatment ofmicrobial infections are increasing because the rate by which bacteriadevelop resistance to current treatment modalities outpaces thedevelopment of new antibiotics. S. aureus is the most common pathogenisolated from patients, and methicillin resistant strains now accountfor approximately 60% of S. aureus isolates in intensive care units inthe US (3). Vancomycin is commonly used to treat serious MRSA infectionsbecause most strains of the pathogen exhibit resistance to many otherclasses of antimicrobials. However, cases of MRSA with reducedsusceptibility or resistance to vancomycin have begun to emerge inhospitals and are associated with increasing patient mortality (4). Thecontinued development of bacterial resistance indicates an urgent needfor treatment approaches that do not rely solely upon antibiotics.

One approach being tested by several groups is photodynamic therapy,which uses light absorbing dyes to generate toxic oxygen radicals tokill the bacteria. However, this treatment might not be effective forinfections in hypoxic wound environments (5). Another promising approachis to use metal nanoparticles, and laser energy to physically damage thebacteria.

The optical properties of conductive metal nanoparticles (NPs), such asthose made of gold and silver have been associated with the surfaceplasmon resonance (SPR) of metals, which when confined to smallcolloids, is referred to as the localized surface plasmon resonance(LSPR). This phenomenon, in which the free electrons oscillatecollectively on the metal surface when irradiated with particularenergies of light, causes wavelength dependent absorption and scatteringof light, and is the source of the colors associated with metalnanoparticles. The size, shape, and composition of the colloidalparticles determines the energy of the SPRs, and therefore, control overthe synthesis of metal NPs provides an ability to tune the opticalproperties of the nanometals contained therein.

Metal nanoparticles, due to their relative inertness, sub-100 nm size,unique electromagnetic properties, and strong optical tunability, haveattracted attention in the biomedical field. For example, because SPRsenhance many optical processes, including Raman scattering,fluorescence, and two-photon excited luminescence, gold NPs have beenused in optical diagnostics and as contrast agents for bioimaging. Whengold NPs absorb light energy, they also release heat, making them usefulin photothermal therapy applications targeting cancer and bacterialcells. Laser-induced photothermal phenomena induce physical disruptionof the bacterial cells leading to death. This is a different type ofkilling mechanism than that caused by antibiotics or photodynamictherapies that induce chemical damage via generation of oxygen radicals.Resistance to photothermal destruction has not been reported in theliterature.

Despite the prospect of biomedical utilizations of metal NPs, the use ofmetal NPs for medical diagnosis and treatment is limited, because NPscannot be fully integrated into the biological realm without changes totheir surface chemistry. Biomolecules interact with cells through amultitude of chemical interactions and physical forces. The interactionsbetween biological systems and metal NPs, on the other hand, arenon-specific. In order to realize the full biomedical potential of metalnanoparticles, the nanoparticles must interact specifically withbiological matter, including cell surface components. At the same time,nanoparticle aggregation and nonspecific interactions with molecular andcellular constituents of the biological system must be minimized. Thus,there is a need in the art for metal nanoparticles that can be readilymodified to precisely control their electromagnetic and biofunctionalproperties.

Zharov et al. taught a method using gold nanospheres and pulsed laserirradiation to induce a photothermal effect for bacterial destruction(5). This method involved a two-step process to bind the particles tothe bacteria, where bacteria were first incubated with primary antibodyagainst S. aureus Protein A in the cell wall then incubated with goldnanospheres coated with a secondary antibody against the primaryantibody. However, the Zharov et al. (5, 7) only tested the techniqueagainst methicillin sensitive bacteria. The method's effectivenessagainst drug resistant bacteria is not addressed. Furthermore, the levelof expression of Protein A, which is the targeted protein of Zharovstudy, has been reported to vary among different strains of MRSA andamong the different phases of growth of the bacteria (6). As a result,the Zharov method is likely to be ineffective against strains or phasesof the bacteria that fails to express Protein A.

DETAILED DESCRIPTION OF DRAWINGS

FIG. 1 Targeted killing of MSSA with antibody functionalized goldnanoparticles.

FIG. 2 Scanning electron microscope images of a) MSSA, b) MSSA+GNPswithout antibody, c) MSSA+GNPs with antibody at 25,000×, d) MSSA+GNPswith antibody at 100,000× magnification, e) MSSA+GNPs with antibody andexposed to sham laser treatment (−Laser), and f) through h) MSSA+GNPswith antibody and exposed to pulsed laser irradiation at 532 nm(+Laser).

FIG. 3 Antibacterial effect of antibody targeted gold nanoparticles andpulsed 532 nm laser irradiation against MSSA as a function of laserfluence.

FIG. 4 Antibacterial effect of targeted GNPs and pulsed 532 nm laserirradiation against A) MSSA and B) MRSA.

DETAILED DESCRIPTION OF THE INVENTION

An objective of this invention is a non-antibiotic treatment method formicrobial infections.

Another objective of this invention is functional antibody coatednanoparticles for selective killing of drug resistant bacteria. Theinventive method simplifies the treatment protocol of Zharov et al. byrequiring attachment of only one antibody, and is effective against bothmethicillin sensitive and resistant bacteria.

Yet another objective of this invention is a method ofdestroying/reducing microbial biofilm using functional antibody coatednanoparticles under exposure of laser irradiation.

Yet another objective of this invention is a method ofdestroying/reducing bacterial infection including infections involvingbiofilm generated by microorganisms using functional antibody coatednanoparticles, in combination with an adjuvant under laser irradiation.

An embodiment of this invention is functional antibody coatednanoparticles comprised of a nanoparticle core; and an antimicrobialantibody coating disposed on at least part of the surface of thenanoparticle core. The nanoparticle core is capable of absorbing laserirradiation, which includes but is not limited to a metal nanoparticle,a nanoparticle with a core-shell structure, or an electroceramicnanocomposite. In one embodiment, the nanoparticle core is a goldnanoparticle or a silica nanoparticle coated with a gold shell. Theantimicrobial antibody is capable of recognizing the targetmicroorganism such as a Gram-positive or Gram-negative bacterium. In oneembodiment, the antibody is capable of recognizing bacteria with surfacepeptidoglycan. The antibody may be coated onto the nanoparticle core viaa variety of attachment methods, including but not limited to covalentbonds, electrostatic interactions, or streptavidin-biotin bond.

The functional antibody coated nanoparticles of this invention may beeasily prepared by a) providing a nanoparticle solution; preparing asolution containing the antibacterial antibody; and reacting saidnanoparticle solution with the antibacterial antibody solution, so theantibacterial antibody is fixed on a surface of the nanoparticle. In oneembodiment of this invention, gold nanoparticle is first coated withstreptavidin. Streptavidin coated gold nanoparticles are purchased fromBIOASSAY WORKS®, LLC (Ijamsville, Md.), and suspended in a phosphatebuffered saline solution containing bovine serum albumin and glycerol tostabilize the nanoparticles against aggregation. An anti-peptidoglycanantibody solution is then prepared, which contains biotinylatedantipeptidoglycan antibody. The two solutions are thoroughly mixed, andthe antipeptidoglycan antibody is fixed onto the surface of thenanoparticle via streptavidin-biotin binding.

The functional antibody coated nanoparticle of this invention may beused to treat microbial infection, such as a bacteria infection. In anembodiment, the subject is first administrated an effective dose of theantibody coated nanoparticles of this invention, and the subject wasplaced under laser irradiation source. The exposure may lastapproximately 1-200 seconds. The laser irradiation source may includebut not be limited to any high energy light source with pulse width lessthan 100 microseconds. The wavelength of the irradiation may be 300 to1500 nm. In one embodiment, a patient was treated for wound surfacebacterial infection by first applying functional antibody coatednanoparticles to the wound, and then irradiating the wound site underhigh peak power pulsed laser for a short time. A pharmaceuticallyacceptable carrier such as a liquid, solution, or aerosol composed ofsterile, isotonic saline, phosphate buffered saline or 0.1% albumin insaline for topical administration, may also be administered with thefunctional antibody coated nanoparticles. One or more antimicrobialagents may also be administered before laser irradiation. For example,Chitosan is a naturally occurring biopolymer with good biocompatibilityand antimicrobial activity against a wide range of bacteria.Endopeptidase lysostaphin can enzymatically attack the bacterial cellwall. Other antimicrobial enzymes, such as dispersin B that breaks downthe extracellular matrix of biofilms, and antimicrobial peptides, suchas LL-37 and ranalexin that weaken the bacterial membrane or cell wall,may also be included.

The functional antibody coated nanoparticles may also be used to preventor reduce biofilm formation generated by a microorganism, such asbacteria. In an embodiment, the subject is administrated an effectivedose of the functional antibody coated nanoparticles of this invention,and subject to laser irradiation. The exposure may last approximately1-200 seconds. The laser irradiation source may include but not limitedany high energy light source with a pulse width less than 100microseconds. The wavelength of the irradiation may be 300 to 1500 nm. Apharmaceutically acceptable carrier such as a liquid, solution, oraerosol composed of sterile isotonic saline, phosphate buffered saline,10% glycerol, or 0.1% albumin in saline for topical administration, mayalso be administered with the functional antibody coated nanoparticles.One or more antimicrobial agents may also be administered before laserirradiation. For example, Chitosan is a naturally occurring biopolymerwith good biocompatibility and antimicrobial activity against a widerange of bacteria. Endopeptidase lysostaphin can enzymatically attackthe bacterial cell wall. Dispersin B is also known to break down theextracellular matrix of staphylococcal biofilms (12). Antimicrobialpeptides such as LL-37 and ranalexin weaken the bacterial membrane orcell wall (13, 14).

Although the embodiment is directed to S. aureus, other bacterialinfections may also be treated using nanoparticles of this invention,such as Acinetobacter baumanii, Pseudomonas aeruginosa, E. coli, andKlebsiella species. Antibodies specific for the infectious agent must beselected to target the nanoparticles to the bacteria. Nanoparticles ofdifferent shapes or sizes must be selected based on the wavelengthselected for the infection to maximize absorption.

Similarly, in additional to treating topical wounds, infection withinthe body such as lung infection caused by tuberculosis may also betreated using the inventive method with minor adaption. The laserwavelength for deeper penetration needs to be in the near infraredregion of 700 to 900 nm. Laser irradiation may be directed to infectionsite via optic fibers.

Example 1

Preparation Of Functionalized Gold Nanoparticles

Fifty μL aliquots (−6.5×10¹⁰ particles) of sterile-filtered 40 nm goldnanospheres coated with streptavidin (15 OD, BioAssay Works, Ijamsville,Md., USA) were diluted with 1 mL of phosphate buffered saline (PBS,Gibco, Grand Island, N.Y., USA) containing 0.1% bovine serum albumin(Sigma, St. Louis, Mo., USA) and 10% glycerol (Sigma, vehicle containingPBS, bovine serum albumin, and glycerol hereafter referred to as PBG)and centrifuged at 7400 g for 10 minutes at room temperature to removethe original vehicle. The supernatant was removed, the pellet wassuspended in 0.5 mL of PBG, and biotinylated anti-Staphylococcus aureusmonoclonal antibody (1.3 mg/mL, Clone 702, Acris Antibodies, San Diego,Calif., USA) was added at a 1:100 volumetric ratio. Non-functionalizedgold nanospheres were prepared in the same way without addition of theantibody. Tubes were then placed on an orbital mixer (Clay Adams NutatorMixer, BD, Franklin Lakes, N.J., USA) for 1 hour at room temperature.

Preparation of Bacterial Cultures

Methicillin sensitive (MSSA, catalog number 29213) and methicillinresistant (MRSA, catalog number 33591) strains of S. aureus wereobtained from the American Type Culture Collection (Manassas, Va., USA)and grown aerobically in tryptic soy broth or nutrient broth (both fromBD), respectively, on a shaking incubator at 250 rpm and 37° C. to anOD600 of 0.500 to 0.550 (−1−2×10⁸ CFU/mL). Cultures were centrifuged at5000 g for 5 minutes at room temperature. The supernatant was removedand the bacterial pellets were suspended in one-half the originalculture volume of PBG. Tubes containing the functionalized ornon-functionalized nanoparticles were removed from the orbital shakerand 0.5 mL of the bacterial suspension was added to each tube. Fornon-treated control samples, 0.5 mL of the bacterial suspension in PBGwas added to a tube containing 0.5 mL of PBG without any nanoparticles.All tubes were then returned to the orbital shaker for 90 minutes ofincubation at room temperature.

Laser-Induced Photothermal Killing of Bacteria

Laser exposures were performed using an Nd:YAG Q-switched laser (modelCRF400, Big Sky/Quantel, Bozeman, Mont., USA) with a wavelength of 532nm, an 8 nanosecond pulse duration, and a pulse repetition rate of 1 Hz.The optical system included a 250-mm focal length lens and a variableaperture arranged to provide a 2-mm diameter beam with a maximum energydensity of approximately 5 J/cm²/pulse. In some experiments, neutraldensity filters were placed in the beam path to reduce the pulse energy.A Nova II Laser Energy Meter with a Pyroelectric Energy Sensor (modelPE25BF-DIF-C) and StarLab 2.0 software (all from Newport, Irvine,Calif., USA) were used to measure and record the pulse energies for eachexperiment. Laser dosimetry was performed immediately pre- andpost-exposure by recording the energy of 10 successive pulses. Thesepre- and post-exposure values were combined to calculate the meanexposure energy, which was used to calculate laser fluence (energy perunit area) assuming a 2-mm beam diameter.

Triplicate or quadruplicate 75-uL aliquots from each bacterial samplewere exposed in quartz cuvettes with a 2 mm wide window and 10 mm lightpath (Precision Cells, Farmingdale, N.Y., USA). For sham exposures,samples were transferred to cuvettes and placed in the exposure set upfor the approximate duration of laser treatment but the laser was notactivated. After irradiation with 100 pulses or sham exposure, thealiquots were transferred to fresh tubes, serially diluted in PBS, andplated in triplicate on tryptic soy agar. Bacterial colonies werecounted after overnight incubation at 37° C. Statistical analysis ofresults was conducted using STATISTICA software (v. 9.1, StatSoft, Inc,Tulsa, Okla., USA).

Results

FIG. 1 shows targeted killing of methicillin sensitive S. aureus (MSSA)with antibody functionalized gold nanoparticles combined with 532 nmlaser irradiation (100 pulses, 5 J/cm2). Bacterial survival wasdetermined by colony forming unit assay. The control group, which didnot receive GNPs or laser treatment, was set to 100% survival. Valuesare expressed as Mean+SD. p=0.0002 compared to the other threeexperimental groups was determined by one-way ANOVA followed by post-hocTukey HSD test. The results shows antibody functionalized goldnanoparticles combined with 532 nm laser irradiation is effective insignificantly reducing bacterial survival.

FIG. 2 is the scanning electron microscope images of a) MSSA, b)MSSA+GNPs without antibody, c) MSSA+GNPs with antibody at 25,000×, andd) MSSA+GNPs with antibody at 100,000× magnification. Images illustrateantibody targeting of GNPs to MSSA. Bottom four panels show MSSA treatedwith antibody-conjugated GNPs and exposed to e) sham treatment (−Laser)or f) through h) pulsed laser irradiation at 532 nm (+Laser). Panels f)through h) show evidence of flattened, dead bacterial cells.

FIG. 3 shows antibacterial effect of antibody targeted goldnanoparticles and pulsed 532 nm laser irradiation against MSSA as afunction of laser fluence. MSSA samples were incubated with 40-nm goldnanospheres coated with anti-S. aureus antibodies then exposed to 100laser pulses. Bacterial survival was determined by colony forming unitassays. The control group which did not receive gold nanoparticles orlaser treatment was set to 100% survival. Values are expressed asMean+SD of six independent experiments.

FIG. 4 shows Antibacterial effect of targeted GNPs and pulsed 532 nmlaser irradiation against A) MSSA and B) MRSA. Bacterial samples wereincubated with 40-nm gold nanospheres coated with anti-S. aureusantibodies then exposed to 100 laser pulses. Bacterial survival wasdetermined by colony forming unit assays. The control group which didnot receive gold nanoparticles or laser treatment was set to 100%survival. The antibody functionalized gold nanoparticles combined with532 nm laser irradiation is shown to be effective in killingdrug-resistant S. aureus.

Prophetic Example 2 Laser-Induced Opto-Acoustic Killing Of S. AureusPlanktonic Cultures

Chitosan is a naturally occurring biopolymer with good biocompatibilityand antimicrobial activity against a wide range of bacteria. The abilityof chitosan to enhance the antibacterial effect of laser-inducedopto-acoustics against methicillin-sensitive and methicillin-resistantS. aureus in planktonic cultures will be tested. First, theanti-bacterial effect of two low molecular weight, and one mediummolecular weight chitosan preparations without laser or nanoparticletreatment will be determined by monitoring OD600 over 24 hours in amicrotiter plate growth assay. The chitosan preparation with thegreatest antibacterial effect in the plate assay will then be tested todetermine if it can augment the laser-induced opto-acoustic killing ofS. aureus. Testing will include experiments to characterize the chitosanconcentrations and incubation times for maximal antimicrobial effect.

Prophetic Example 3 Laser-Induced Opto-Acoustic Treatment To Destroy S.Aureus Biofilms Develop An In Vitro S. Aureus Biofilm Model

An in vitro biofilm model will be developed using methicillin-sensitiveand methicillin-resistant strains of S. aureus, according to publishedprocedures (8, 9). In brief, aliquots of fresh bacterial cultures inbroth will be inoculated into wells of 96-well microplates with quartzbottoms and incubated for 24 to 48 hours as needed for formation ofbiofilms. Light microscopy and crystal violet staining will be used tomonitor biofilm formation.

Gold nanospheres coated with streptavidin will be functionalized asdescribed using biotinylated monoclonal antibodies directed againstpeptidoglycan, protein A, or lipoprotein of S. aureus (10, 11).Methicillin-sensitive and methicillin-resistant S. aureus biofilms willbe grown in 96-well microplates as described. Broth will be removed fromthe wells and the plates and washed with PBS. Aliquots of thefunctionalized nanospheres will then be added to the microplate wellscontaining biofilms and the plates will be incubated for 90 minutes at37° C. The nanoparticle solution will be removed, the wells washed withPBS, and fresh PBS added to the wells. The plates will be placed in acustom-designed 96-well plate holder attached to a computer-controlledgantry XY robotic system and exposed through the top of the well to 8-nspulsed laser irradiation at 532 nm. Sham exposed samples will be placedwithin the sample holder but the laser will not be activated. Totalbiofilm mass will be measured using the crystal violet staining method(9), and selected biofilm samples will be analyzed for bacterialviability using a LIVE/DEAD Biofilm Viability Kit (Invitrogen). Efficacyof the three different types of monoclonal antibodies in targeting thenanoparticles to induce killing of the biofilms will be compared.

Use of adjuvants that are known to weaken the bacterial cell wall andextracellular matrix of biofilms will potentially make the cells moresusceptible to the opto-acoustic effects and lower the pulse energyrequired for maximal anti-bacterial effect. At this time, possiblecandidates selected for testing as adjuvants include the endopeptidaselysostaphin, which enzymatically attacks the bacterial cell wall anddispersin B, an enzyme that breaks down the extracellular matrix ofstaphylococcal biofilms (12). Other possible candidates includeantibacterial peptides that weaken the cell wall or membrane suchranalexin and LL-37 (13, 14).

REFERENCES

-   1. Petersen K, Riddle M S, Danko J R, Blazes D L, Hayden R, Tasker S    A, Dunne J R. Trauma-related infections in battlefield casualties    from Iraq. Ann Surg. 2007;245(5):803-811.-   2. Peterson K, Hayes D K, Blice J P, Hale R G. Prevention and    management of infections associated with combat-related head and    neck injuries. J Trauma. 2008;64(3):S265-S276.-   3. Boucher H W, Corey G R. Epidemiology of methicillin-resistant    Staphylococcus aureus. Clin Infect Dis. 2008;46 Suppl 5:S344-349.-   4. Sakoulas G, Moellering R C, Jr. Increasing antibiotic resistance    among methicillin-resistant Staphylococcus aureus strains. Clin    Infect Dis. 2008;46 Suppl 5:S360-367.-   5. Zharov V P, Mercer K E, Galitovskaya E N, Smeltzer M S.    Photothermal nanotherapeutics and nanodiagnostics for selective    killing of bacteria targeted with gold nanoparticles. Biophys J.    2006;90(2):619-627.-   6. Embleton M L, Nair S P, Cookson B D, Wilson M. Selective lethal    photosensitization of methicillin-resistant Staphylococcus aureus    using an IgG-tin (IV) chlorin e6 conjugate. J Antimicrob Chemother.    2002;50(6):857-64.-   7. Galanzha E I, Shashkov E, Sarimollaoglu M, et al. In vivo    magnetic enrichment, photoacoustic diagnosis, and photothermal    purging of infected blood using multifunctional gold and magnetic    nanoparticles. PLoS One. 2012;7(9):e45557.-   8. Sanchez C J Jr, Mende K, Beckius M L, Akers K S, Romano D R,    Wenke J C, Murray C K. Biofilm formation by clinical isolates and    the implications in chronic infections. BMC Infect Dis. 2013;13:47.-   9. Chen P, Abercrombie J J, Jeffrey N R, Leung K P. An improved    medium for growing Staphylococcus aureus biofilm. J Microbiol    Methods. 2012;90(2):115-8.-   10. Galanzha E I, Shashkov E, Sarimollaoglu M, Beenken K E,    Basnakian A G, Shirtliff M E, Kim J W, Smeltzer M S, Zharov V P. In    vivo magnetic enrichment, photoacoustic diagnosis, and photothermal    purging of infected blood using multifunctional gold and magnetic    nanoparticles. PLoS One. 2012;7(9):e45557.-   11. Brady R A, Leid J G, Kofonow J, Costerton J W, Shirtliff M E.    Immunoglobulins to surface-associated biofilm immunogens provide a    novel means of visualization of methicillin-resistant Staphylococcus    aureus biofilms. Appl Environ Microbiol. 2007;73(20):6612-9.-   12. Kiedrowski M R, Horswill A R. New approaches for treating    staphylococcal biofilm infections. Ann N Y Acad Sci.    2011;1241:104-21.-   13. Graham S, Coote P J. Potent, synergistic inhibition of    Staphylococcus aureus upon exposure to a combination of the    endopeptidase lysostaphin and the cationic peptide ranalexin. J    Antimicrob Chemother. 2007 Apr;59(4):759-62.-   14. Vandamme D, Landuyt B, Luyten W, Schoofs L. A comprehensive    summary of LL-37, the factotum human cathelicidin peptide. Cell    Immunol. 2012 Nov;280(1):22-35.

What is claimed is: 1) A functional antibody coated nanoparticle,comprising: a. a nanoparticle core; and b. an antibody coating disposedon at least part of the surface of said nanoparticle core, wherein thecoating comprises an antimicrobial antibody capable of recognizing atarget bacteria. 2) The nanoparticle according to claim 1, wherein thenanoparticle core is capable of absorbing laser irradiation. 3) Thenanoparticle core according to claim 2, wherein the nanoparticles coreis a metal nanoparticle, a nanoparticle with a core-shell structure, oran electroceramic nanocomposite. 4) The antibody according to claim 3,wherein the nanoparticle core is a gold nanoparticle or a silicananoparticle coated with a gold shell. 5) The antibody according toclaim 1, wherein the antibody is capable of recognizing Gram-positivebacteria or Gram-negative bacteria. 6) The antibody according to claim1, wherein the antibody is capable of recognizing bacteria with surfacepeptidoglycan. 7) A method of preparing functional antibody coatednanoparticles of claim 1, comprising: a. providing a nanoparticlesolution; b. preparing a solution containing antimicrobial antibody; andc. reacting said nanoparticle solution with the antimicrobial antibodysolution, wherein the antimicrobial antibody is fixed on a surface ofthe nanoparticle. 8) The method according to claim 7, wherein thenanoparticle is a metal nanoparticle, a nanoparticle with a core-shellstructure, or an electroceramic nanocomposite. 9) The method accordingto claim 8, wherein the nanoparticle is a gold nanoparticle or a silicananoparticle coated with a gold shell. 10) The method according to claim7, wherein the nanoparticle is coated with streptavidin. 11) The methodaccording to claim 10, wherein said antimicrobial antibody isbiotinylated. 12) The method according to claim 7, wherein saidantimicrobial antibody is an anti-peptidoglycan antibody. 13) The methodaccording to claim 7, wherein said nanoparticle solution furthercomprises phosphate buffered saline, bovine serum albumin and glycerol.14) A method of using the functional antibody coated nanoparticleaccording to claim 1 to treat microbial infection, comprising a.administrating an effective dose of the antibody coated nanoparticles toa subject in need thereof, and b. exposing the subject under laserirradiation source. 15) The method according to claim 14, wherein thelaser irradiation source is high peak power pulsed laser. 16) The methodaccording to claim 14, further comprising coadministering one or moreantimicrobial agent to the subject before laser irradiation. 17) Themethod according to claim 16, wherein said antimicrobial agent isendopeptidase lysostaphin, Chitosan, dispersin B, ranalexin, or LL-37.18) A pharmaceutical composition for treating microbial infection,comprising the functional antibody coated nanoparticle according toclaim 1, and a pharmaceutically acceptable carrier thereof. 19) A methodof using the pharmaceutical composition according to claim 18 to treatmicrobial infection, comprising administrating the pharmaceuticalcomposition with an effective dose to a subject in need thereof, andexposing the subject laser irradiation. 20) The method of claim 18,wherein said laser irradiation is of wavelength of 300 to 1500 nm. 21)The method of claim 18, wherein said pharmaceutical composition iscoadministered with one or more antimicrobial agent. 22) The method ofclaim 21, wherein said antimicrobial agent is endopeptidase lysostaphin,Chitosan, dispersin B, ranalexin, or LL-37. 23) A method for preventingor reducing formation of a biofilm generated by a microorganism,comprising a. administrating an effective dose of the antibody coatednanoparticles of claim 1 to a subject in need thereof, and b. exposingthe subject to a laser irradiation source. 24) The method according toclaim 23, wherein the laser irradiation source is high peak power pulsedlaser. 25) The method according to claim 24, further comprisingcoadministering one or more antimicrobial agent to the subject beforelaser irradiation. 26) The method according to claim 25, wherein saidantimicrobial agent is endopeptidase lysostaphin, Chitosan, dispersin B,ranalexin, or LL-37. 27) The method of claim 23, wherein said laserirradiation is of wavelength of 300 to 1500 nm.